COMBINATION OF INSECTICIDE APPLICATIONS WITH TRAP CROPS OF EARLY MATURING SOYBEAN AND SOUTHERN PEAS FOR POPULATION MANAGEMENT OF NEZARA VIRIDULA IN SOYBEAN1,2 (HEMIPTERA: PENTATOMIDAE)
Early maturing soybean, Glycine max, cultivars and southern peas, Vigna unguiculata, were used as trap crops in large scale field tests for Nezara viridula population management in soybean. In a 1979 test, the ‘Dare’ trap crop reached R5 (podfill) ca. 2 weeks prior to ‘Bragg’, and was infested with a much larger stink bug population. Southern peas and ‘Coker 156’ soybean were used in four field tests in 1981, and results indicated that insecticide treatments applied to the trap crop when the main crop ‘Bragg’ was in R3-R4 (podset) stage were applied too late, thereby allowing stink bug populations in each field to develop to high population levels. These results indicate that chemical controls should be applied to the trap crop before 5th stage nymphs change to adults with much greater dispersal capability and sexual maturity. Additionally, treatment of the trap crop should occur before the main crop enters the R3-R4 stage of development, since oviposition by female N. viridula is known to be greatly intensified in soybean in that phenological stage.